7,894 youth football players are playing in the US
It really depends on the type. Youth leagues in the US practice up to 3 hours a week, Youth leagues in Europe practice up to 6 to 7 hours a week, pro leagues in Europe practice 10+ hours a week.
There 12 leagues, all in Pennsylvania.
3 in all professional leagues, and in the us the youth and high school there are unlimited. not sure about the ncaa rules tho
probably basketball or football
Probably on US bases with schools, but I never saw a European play football when I lived there.
For Youth, I believe it may be football.
The Negro leagues were US professional baseball leagues. The term is usually used to include 7 leagues, also called "Negro Major Leagues" which began in 1920.
Why not? There are now over 100 teams women's tackle football teams in the US. The most common response from a doubter after seeing them play - "Wow, it's real tackle football!" In the main women's tackle football leagues in the US it's full gear, full tackle football, just like the men play. The only difference besides being women vs men is the women typically play with a smaller ball (the junior or youth version.)
They can and do. Whole leagues are for women only. This assumes you are not from the US, though, where football - meaning American football there - is frowned upon as a female's game; association football is very popular among females there instead.